I know it's a food item, but is it used for anything else, like an achievement? I've had it on my wishlist for a while and I can't remember why.

definitely not used for any achievements (other than as a generic unique food item for gourmand). Nor does it have any official use other than food.

[edit] Also not a genetech ingredient or baking ingredient (Vetan Beer Bread uses free beer).

It is easy to accidentally click the 'add to wishlist' section on the bottom of every item image. I found three ??? items in my WL when I checked just now.

I found why I had that beer on my wishlist! I was collecting them up for the Drunk Gunter achievement. You can give him any beer items; I was just collecting that one because it's super cheap during Neugarten. Mystery solved! :D

Yay! Always fun to solve a mystery :D